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Mod | | | Forums66 Topics128,031 Posts1,055,436 Members48,422 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2013 Posts: 168 Shop Shark | | Shop Shark Joined: May 2013 Posts: 168 | Hello all, I have a 1953 3100, and am putting it back together. I have a new wiring harness, but it doesn't show one item that is installed on my firewall. It is the black box on the bottom left side. Item I've looked in the shop manual, but don't find it. From the pic, it seems that maybe it is going to the horns. Not sure...any ideas? Thanks, Steven
1953 3100
Melbourne, FL Veteran
| | | | | Joined: Jun 2006 Posts: 693 'Bolter | | 'Bolter Joined: Jun 2006 Posts: 693 | if i had to guess - i'd say its an aftermarket voltage regulator ("VR"). can't conceive of any other device that would need to be rated 32-42 amps | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | "VR" would indicate a voltage regulator, and it looks about the right size and shape - is there another similar that's the voltage regulator?
Bill | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I think that is a horn relay. That regulator is not a GM regulator. Do you have a Delco generator? | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | 1953 and later horn relay (also used as the relay for optional dual horns 47-52).
| | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | "It is the black box on the bottom left side."
I agree it is the horn relay.
I'll bet the guys that said voltage regulator didn't do well on the reading comprehension tests.
| | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | or maybe the guys who saw a picture of just a black box didn't think it might be only a portion of the original picture  Bill | | | | | Joined: May 2013 Posts: 168 Shop Shark | | Shop Shark Joined: May 2013 Posts: 168 | Thanks guys. It had dual horns on it, and so a dual horn relay makes sense. I'll just put one of the dual horns back on, as it is the only one that I can get working right now. I suppose that I will still need to run it through the relay. Will give a try when I get to that point.
Thanks
1953 3100
Melbourne, FL Veteran
| | | | | Joined: Mar 2011 Posts: 1,146 Shop Shark | | Shop Shark Joined: Mar 2011 Posts: 1,146 | 1953 and later horn relay (also used as the relay for optional dual horns 47-52). Tim, Was it required to have a special horn relay when you have the dual horns? Is there a dual horn wiring diagram some where? | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | jorb, I do not know if it was "required" but it was standard equipment in/with that GM accessory Matched Horns (dual horns). Look at step #4. | | | | | Joined: Mar 2011 Posts: 1,146 Shop Shark | | Shop Shark Joined: Mar 2011 Posts: 1,146 | You just jogged my memory. Now I remember where I've seen that before. In the 1954 Chevrolet Accessories Booklet. page 53 And the 47-54 Factory Assembly Manual. Section 11 sheet 30 RPO 430 & 431 This Diagram shows one horn. This Diagram shows one horn but I have to rotate my screen to read it. I thought there was a 1954 Chevrolet Accessories Booklet on chevy.oldcarmanualproject.com I assume all horns have a relay no matter if there are one or two horns. Another thing I just learned. There is a matched horn accessory 986397 And a add on high note horn accessory 986893 or RPO 430 & 431 to the already existing low note horn.
Last edited by jorb; 04/19/2014 2:12 AM. Reason: Error on 1st link , Redid
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | All horns (single and dual) had a relay from 1953 onwards. 1953 was the first year that a "low note" "seashell" horn was standard (mounted on the intake manifold).
The accessory "add-on" high note "seashell" horn was a 1953-55st accessory
Earlier (pre-1953) standard, single horns on trucks did not come with a relay.
The 1947-52 accessory "matched horns" were two "seashell" style horns (and this set came with a relay).
Your first link to Photobucket does not work for me ("Photobucket Exception" unexpected error occurred).
| | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | I just want a moooooo horn. Or maybe the Geico pig weeeeeeeeee! I dunno. Maybe Joan Rivers voice saying.. Hello? Moron! Get out of the freakin way! Naw... maybe Howards mom on Big Bang theory yelling HOWARD! or Sheldon saying PENNY..PENNY..PENNY.. LOL!
Someday, I will be concerned with horns. Right now I am still working on the body work. I have always wondered why, if you need a horn relay, doesn't it come as part of the horn? | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Both of those links work for me. Thanks
| | | | | Joined: Jun 2012 Posts: 1,747 'Bolter | | 'Bolter Joined: Jun 2012 Posts: 1,747 | OK so now I am confused. Not about the horn relay. I have seen lots of them, but all the ones I have seen were mounted to the screws at the top of the V. R. So now I have to look for that lower mount by the fuse block? This "Period Correct" thing is making my head hurt. That is what PC stands for, correct?
Steve H
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